Hydraulic and spring operated expansive reamer



J. GRANT Oct. 29, 1935.

HYDRAULIC AND SPRING OPE/RATED EXPANSKIVE BEAMER Filed oct. 26a 1934 fly! Patented Oct. 29, 1935 UNITED STATES HYDRAULIC AND SPRING OPERATED EXPANSIVE BEAMER John Grant, Los Angeles, Calif.

Application October 26, 1934, Serial No. 750,060

14 Claims.

This invention has to do with expansive reamers of the type used for a reaming operation in deep wells; and it is a general object of the invention to provide an expansive reamer of sim- 'I ple and strong construction, and one which may be operated either by a spring or by hydraulic pressure or both.

How these and other objects are accomplished, and the advantageous features of the invention, will be best understood from the following detailed description wherein a preferred and illustrative embodiment is set forth, reference for this purpose being had to the accompanying drawing in which:

Figs. 1 and 2 are longitudinal central sections showing the illustrative reamer in expanded and collapsed positions, respectively;

Fig. 3 is a cross section on line 3-3 of Fig. 1; and

Fig. 4 is a fragmentary section showing a variational form of assembly.

In the drawing I show the body of the underreamer composed of an upper part I and a lower part II, part I0 having a longitudinal central bore I2 and part II having a longitudinal central bore I3, Ia. The two body parts are screwthread'edly joined at I4, and, in eifect, together form a solid body with an internal longitudinal bore.

In this hollow body there is an abutment member I 5 which is also formed preferably as a separate part, but in effect may be considered either as a separate piece or as a stationary part of the body. Preferably this abutment member l5 lies in bore I3a of the lower body member and is held in place by the threaded juncture I 'I with the upper body member I0.

This abutment member has opposite upwardly and rather sharply outwardly inclined faces I8 at its lower end, and has opposite upwardly and outwardly inclined faces I9 above the faces I8. TheA cutters, here generally designated by the letter C, ride at their upper ends upwardly and outwardly over the faces I8 and I9, and when they reach their uppermost expanded positions of Fig. l, they bear inwardly against the abutment faces I9.

The cutters may be of any kind or type desired; they are here shown as composed of carriers 20, made up of slide blocks w and spindles 20h, and roller cutter elements 2| rotatably mounted on spindles 20h. The carriers 20' ride in the longitudinal body slots 23 and have laterally extending flanges 22 (Fig. 3) which engage the miy inner wall surface of the body, so as to limit the (Cl. Z55-75) outward movement of the cutters to positions shown in Fig. 1. When the cutters are in their uppermost expanded positions, the upper ends of the cutters are held solidly against either inward or outward movement by the action of the 5 flanges and of the abutment member I5.

In the design hereillustrated, the lower ends of the cutters do not move outwardly; the cutters tilt outwardly at their upper ends as they rise. The lower ends of the carriers 20 rest upon 10 a supporting and abutment member which has upwardly facing shoulders 24 upon which the carriers rest and outwardly facing shoulders 24a against which the lower ends of the carriers bear inwardly. When the cutters are expanded, their 15 anges at the lower ends bear outwardly against the body wall, and the lower ends of the carriers bear inwardly against the member 25, thus solidly holding the lower ends of the cutters against either inward or outward movement as is best 0 seen from Figs. 1 and 3.

The cutter supporting and abutment member 25 is preferably made integral with a piston 26, so that the forces exerted by the piston will be transmitted directly to member 25 without the 25 intervention of any other force transmission member between them. Piston 26, and therefore also member 25, moves vertically in the lower body bore I3; a cup leather or equivalent packing 2'I being provided to make a substantially fiuidtight fit between the piston and the wall of the bore.

The upper end of the tool is adapted as at 30 for attachment to a hollow drill stem or drill pipe through which circulating fluid is forced to the tool. The lower end of the tool is adapted as at 3l for attachment to a drill bit to which the circulating fluid is transmitted. To provide for transmission of such circulating iiuid longitudinally through the tool, and also to provide an operating rod which facilitates operation of the reamer by a spring as well as by fluid pressure,

I provide an operating rod in the form of a vertically movable tube 35 which passes and moves vertically through a central bore 36 in abutment 45 member I5. The lower end of this movable tube 35 is screwthreadedly attached at 3l to the composite member 25-26, and extends on through that member to deliver circulating fluid to the bore i3 below piston 26. The upper end of the operating tube 35 extends into bore I 2 above abutment member I5, and a nut 38 screwthreaded to its upper end affords a shoulder to take the upward pressure of a coil spring 39 which is seated at its lower end either on the shouldered lower end of bore I2 or on the upper end of abutment member I5.

In operation the cutters may be operated to their expanded position either by the spring or by fluid pressure on the piston, or by a combination of both. The spring may be of such compressive strength and may be put under such initial compression that it either tends strongly or only relatively weakly to move the cutters up to their expanded positions. In practice it may be desirable to so choose and adjust the spring that it will not act as strongly as such springs do in a solely spring-expanded reamer, thus to minimize the pressures tending to force the cutters outwardly as they are being put down or drawn out through a casing. At the same time a somewhat relatively weak spring-action will reinforce the fluid pressure acting on the lower end of the piston to make expansion of the cutters just ascertain as it is in the usual strong spring-expansive action. Or, if the spring is chosen and adjusted to be equal to the usual spring strength, then the combined .action of the spring and the fluid pressure on the under side of the piston provides an increased total expansive force that makes the cutter expansion certain.

It will be understood of course that hydraulic pressure is not usually applied to the tool until it has reached the position in the hole where it is desired to expand the cutters. Then, when the hydraulic pressure is applied, a certain proportion of that pressure is always present in bore I3 and active upon piston 26, due to the fact that a drill D or some other equivalent tool is usually attached at 3|, having a somewhat restricted fluid passage or passages 40.

The upper ends of spindles 20h are provided with lugs 40a which, with the upper end faces of the cutter carriers, present upper cam faces 4I whichV incline downwardly and outwardly. When the cutters are in collapsed position the lugs lie within recesses 23, but when the reamer is eX- panded the lugs extend radially beyond the reamer body. Upon completion of the reaming operation, withdrawal movement of the tool engages the lower end of the casing shoe (not shown) through which the tool has been previously lowered, with cam faces 4 I', forcing the carriers downwardly and their upper ends inwardly to the position of Fig. 2. Y

In Fig. 4 is shown a variation wherein abutment Ia is unthreaded, it being held in position by clamping its flange 43 between the lower end of part Ilia and the upwardly facing shoulder 44 of part I Ia. Y

I claim:

1. In an expansive reamer of the character described, a body with a central bore and cutter slots, cutters movable upwardly and outwardly in the slots,'abutment means in the body against which the upper ends of the cutters bear inwardly and by which such' upper ends are held outwardly, a vertically movable piston in the body bore below the cutters, a cutter abutment'and support associated with the piston and against which the cutters shoulder both inwardly and downwardly, and means to apply fluid pressure to the lower face of the piston to move the cutters upwardly.

2. In an expansive reamer of the character described, a body with a central bore and cutter slots, cutters movable upwardly and outwardly inthe slots and projecting into the body bore, abutment means in the body having upwardly and outwardly inclined surfaces upon which the upper ends of the cutters bear inwardly, a cutter abutment and support movable vertically in the body bore at the lower ends of the cutters, said lower ends shouldering both down and inwardly on said abutment and support, and means for moving the abutment and support upwardly, said lower ends of the cutters being held against substantial movement radially of the body during upward movement of the abutment and support relative thereto.

3. In an expansive reamer of the character described, a body with a central bore and cutter slots, cutters movable upwardly and outwardly in the slots and projecting into the body bore, abutment means in the body having upwardly and outwardly inclined surfaces upon which the upper ends of the cutters bear inwardly, a cutter abutment and support movable vertically in the body bore at the lower ends of the cutters, said lower ends shouldering both down and inwardly on said abutment and support, and means for moving the abutment and support upwardly comprising a piston in the body bore associated with the abutment and support, and means to apply fluid pressure to the lower face of the piston.-

4. In an expansive reamer of the character described, a body with a central bore and cutter slots, cutters movable upwardly and outwardly ln the slots and projecting into the body bore, abutment means in the body having upwardly and outwardly inclined surfaces upon which the upper ends of the cutters bear inwardly, a cutter abutment and support movable vertically in the body bore at the lower ends of the cutters, said lower ends shouldering both down and inwardly on said abutment and support, and means including a spring for moving the abutment and support upwardly, said lower ends of the cutters being held against substantial movement radially oi the body during upward movement of the abutment and support relative thereto.

5. In an expansive reamer of the character described, a body with a `central bore and cutter slots, cutters movable upwardly and outwardly in the slotsand projecting into the body bore, abutment means in the body having upwardly and outwardly inclined surfaces upon which the upper ends of the cutters bear inwardly, a cutter abutment and support movable vertically in the body bore at the lower ends of the cutters, said lower ends shouldering both down and inwardly on said abutment and support, and means for moving the abutment and support upwardly, comprising a spring and a piston associated with the abutment and support, and means to apply fluid pressure to the lower face of the piston.

6. In an expansive reamer of the character described, a body with a central bore and with cutter slots through its wall, cutters movable upwardly and outwardly in the slots, projecting into the body bore and having lateral flanges inside the body wall to limit outward cutter movement, a central abutment member in the body bore having upwardly and outwardly inclined faces against which the upper end of the cutters bear inwardly, and whereby the cutter flanges at their upper ends are held outwardly against the body wall, a vertically movable central cutter abutment and support member in the body bore at the lower ends of the cutters, the cutters shouldering down on said member and bearing inwardly on it, the abutment faces of said member being so spaced as to hold the cutter flanges outwardly against the body wall, and means to move said member upwardly.

Vrl. In an expansive reamer of the character described, a body with a central bore and with cutter slots through its wall, cutters movable upwardly and outwardly in the slots, projecting into the bodybore and having lateral flanges inside the body wall to limit outward cutter movement, a central abutment member in the body bore having upwardly and outwardly inclined faces against which the upper end of the cutters bear inwardly, and whereby the cutter flanges at their upper ends are held outwardly against the body wall, a vertically movable central cutter abutment and support member in the body bore at the lower ends of the cutters, the cutters shouldering down on said member and bearing inwardly on it, the abutment faces of said member being so spaced as to hold the cutter flanges outwardly against the body wall, and means to move said member upwardly, comprising a piston in the body bore associated with said member, and means to Eapply, fluid pressure to the lower face of the piston.

8. In an expansive reamer of the character described, a body with a central bore and with cutter slots through its wall, cutters movable upwardly and outwardly in the slots, projecting into the bodybore and having lateral flanges inside the body wall to limit outward cutter movement, a central abutment member in the body bore having upwardly and outwardly inclined faces against which the upper end of the cutters bear inwardly, and whereby the cutter flanges at their upper ends are held outwardly against the body wall, a vertically movable central cutter abutment and support member in the body bore at the lower ends of the cutters, the cutters shouldering down on said member and bearing inwardly on it, the abutment faces of said member being so spaced as to hold the cutter flanges outwardly against the body wall, and means to move said member upwardly, comprising a spring.

9. In an expansive reamer of the character described, a body with a central bore and cutter slots through its wall, cutters movable upwardly and outwardly in the slots, an internal abutment member in the body having upwardly and outwardly inclined faces upon which the cutters move upwardly and outwardly, a vertically movable hollow cutter operating rod central of the body, a cutter supporting and piston member fixed on the cutter operating rod and fitting the body bore and acting to lift the rod and cutters, and a spring in the body acting on the rod to lift it and the cutters.

10. In an expansive reamer of the character described, a body with a central bore and cutter slots through its wall, cutters movable upwardly and outwardly in the slots, an internal abutment member in the body having upwardly and outwardly inclined faces upon which the cutters move upwardly and outwardly, a vertically movable hollow cutter operating rod central of the body, passing vertically through the abutment and extending into the body bore above and below the abutment, a spring acting on the upper end of the rod to lift it, a piston xed to the lower end of the rod and acting when fluid pressure is applied to its lower face to lift the rod, and means associated with the piston and rod supporting the cutters.

11. vIn an expansive reamer of the character described, a body with a central bore and with cutter slots through its wall, cutters movable upwardly and outwardly in the slots, projecting into the body bore and having lateral flanges lying inside the body wall to limit outward cutter movement, a central cutter abutment in the body bore near the upper ends of the slots, having upwardly and outwardly inclined vabutment faces against which the upper ends of the cutters bear inwardly, the abutment having a central bore through it, a hollow cutter operating rod in the abutment bore and extending into the body bore above and below the abutment, a spring acting on the upper end of the rod to lift it, and a piston and associated cutter abutment and support mounted on the lower end of the rod in the body bore.

12. In an expansive reamer of the character described, a body with a central bore and with cutter slots through its wall, cutters movable upwardly and outwardly in the slots, projecting into the bodybore and having lateral flanges lying inside the body wall to limit outward cutter movement, a central cutter abutment in the body bore near the upper ends of the slots, having upwardly and outwardly inclined abutment faces against which the upper ends of the cutters bear inwardly, the abutment having a central bore through it, a hollow cutter operating rod in the abutment bore and extending into the body bore above and below the abutment, a spring acting on the upper end of the rod to lift it, and a piston and associated cutter abutment and support mounted on the lower end of the rod in the body bore, the cutters shouldering both downwardly and inwardly against said abutment and support and being held outwardly thereby so that their fianges at the lower ends are held outwardly against the body wall.

13. In an expansive reamer of the character described, a body with a central bore and cutter slots, cutters movable upwardly and outwardly in the slotsl abutment means in the body against which the upper ends of the cutters bear inwardly and by which such upper ends are held outwardly, a vertically movable piston in the body bore below the cutters, a cutter abutment and support associated with the piston and against which the cutters shoulder both inwardly and downwardly, means to apply fluid pressure to the lower face o-f the piston to move the cutters upwardly, and upwardly presented shoulders on said cutters adapted to extend radially beyond the body when the reamer is expanded.

14. In an expansive reamer of the character described, a body with a central bore and cutter slots, cutters movable upwardly and outwardly in the slots, abutment means in the body against which the upper ends of the cutters bear inwardly and by which such upper ends are held outwardly, a vertically movable piston in the body bore below the cutters, a cutterv abutment and support associated with the piston and against which the cutters shoulder both inwardly and downwardly, means to apply fluid pressure to the lower face of the piston to move the cutters upwardly, and upwardly presented shoulders on said cutters adapted to extend radially beyond the body when the reamer is expanded, said ,shoulders inclining downwardly and outwardly.

J OHN GRANT. 

